By MICHAEL FALCONE ( @michaelpfalcone )

NOTABLES

• OBAMA: INVASION OF UKRAINE 'WILL BE A COSTLY PROPOSITION FOR RUSSIA'. President Obama had more stern warnings for Moscow yesterday, saying the United States will take actions to "isolate" Russia if it continues its occupation of Ukraine's Crimean Peninsula, ABC's MARY BRUCE reports. "If, in fact, they continue on the current trajectory that they're on, that we are examining a whole series of steps - economics, diplomatic - that will isolate Russia and will have a negative impact on Russia's economy and its standing in the world," the president said. "Over time this will be a costly proposition for Russia, and now is the time for them to consider whether they can serve their interests in a way that resorts to diplomacy as opposed to force," he added. http://abcn.ws/1dUQGSC

• THE SANCTIONS GAME: The president's comments at the White House came as the State Department said it was "likely" that the U.S. would pursue economic sanctions against Russia. Obama also urged lawmakers to act quickly to pass an assistance package for the Ukrainian government. "I would hope that that would be the first order of business, because at this stage, there should be unanimity among Democrats and Republicans that when it comes to preserving the principle that no country has the right to send in troops to another country unprovoked, we should be able to come up with a unified position that stands outside of partisan politics. And my expectation is, is that I'll be able to get Congress to work with us in order to achieve that goal," he said.

THE ROUNDTABLE

ABC's JEFF ZELENY: The warning signs are blinking brightly for Democrats in this midterm election year, but that's not the only sentiment influencing this campaign season. The anti-incumbent fervor is running dangerously high for office holders in both parties. A new ABC-Washington Post poll finds that nearly 7 in 10 Americans are open to electing someone new this fall, with only 22 percent saying they are inclined to stick with the incumbent. It's the lowest number ever recorded in an ABC-Post poll. It's a reminder that some incumbents in both parties could be swept away by a tide of discontent. Even though the GOP holds the upper hand in the midterm Congressional elections, the road to November is not an easy one for incumbents who have voting records to defend, even Republicans.

ABC's RICK KLEIN: The tea party may well go 0-for-Texas today, a tough draw in the nation's largest red state, which famously sent Ted Cruz to the Senate less than two years ago. The signs of weaker tea are elsewhere, too; only 8 percent of voters call themselves strong tea party backers in the new ABC News/Washington Post poll, a new low. And Republicans by a 47-41 margin say it's a bad thing for tea party candidates to challenge incumbent Republicans, a reaction, surely, to the missed chances of 2010 and 2012. But don't think that Texas Republicans are therefore taking a moderate turn. As The Dallas Morning News points out, the GOP is set to put forward one of the most conservative slates in memory, even if Steve Stockman and Katrina Pierson are left at home. Tea partiers may fall short today because they succeeded too well in getting establishment candidates to move their way. Cruz control is powerful, at least inside GOP primaries.

TEXAS PRIMARY 2014: 6 THINGS TO WATCH FOR. The midterm election officially gets underway today as Texas hosts the first primaries in the country. The primary races in the Lone Star state will offer an initial glimpse at some of the key trends in the 2014 primaries, including the establishment vs. Tea Party fight and the newcomers who're trying to oust aging incumbents. The contests will also shed light on how the ascension of Sen. Ted Cruz, R-Texas, has influenced politics in Texas. Here's ABC's ARLETTE SAENZ's look at six things to watch for in the Lone Star state's primaries today. http://abcn.ws/1eQYCIN

BUZZ

KERRY: TIME TO 'SEIZE THE DIPLOMATIC MOMENT' IN IRAN, MIDDLE EAST. Secretary of State John Kerry said yesterday all the conditions are ripe for successful negotiations for both halting Iran's nuclear program and reaching peace between Israelis and Palestinians, ABC's ALI WEINBERG notes. Addressing the annual American-Israel Public Affairs Committee Conference, Kerry said it was time to "seize the diplomatic moment" and remain at the negotiating table with all parties as long as possible. Kerry said that tough sanctions had brought Iran to the negotiating table, and that it was time now to exhaust the possibility of a diplomatic solution to Iran's desire to enrich uranium and plutonium. "It is crucial that we seize what might be the last best chance to have diplomacy work," Kerry said, adding that if a good-faith effort at negotiation fails, it will provide justification for more forceful options if necessary. Right after his speech, Kerry departed for a flight to Kiev, Ukraine, where he is meeting with members of the transitional government today. http://abcn.ws/No9YJz

-NOTED: HOW COULD THE G-8 KICK RUSSIA OUT? The Obama administration has said one of its most powerful tools for punishing Russia's violations of Ukrainian sovereignty is the threat of kicking Russia out of the Group of 8 industrialized nations or G-8, ABC's ALI WEINBERG notes. A senior administration official warned Sunday that Russia would "not have a role to play" in the group if it continues its incursion into the Ukrainian region of Crimea. But how would kicking Russia out actually work? There's no formal enforcement mechanism for removing a country from the G-8, which has been meeting since 1975, so all the other countries have to do is not invite Russia to their party. If the other seven countries agreed to leave Russia out, they could simply resume meeting as the G-7, which is what they were before Russia joined the group in 1998, said Bruce Jones, a former senior adviser for both the World Bank and the United Nations. Failing broad consensus, the United States might also just start skipping the party if Russia is going to be there. http://abcn.ws/OUvo21

SIX COUNTRIES THAT TOTALLY IGNORED OBAMA'S DEMANDS. It was a complete rebuff issued with blinding speed: Less than 24 hours after President Obama went on national television on Friday to warn Vladimir Putin that "there will be costs for any military intervention," Russia's military seized total control of Crimea. It's embarrassing for a world power to see its warnings so cavalierly disregarded - and not just when it comes to Russia and Ukraine. During his second term, President Obama has repeatedly found that the sternest warnings and firmest demands from the United States have been ignored with impunity. Consider these examples from ABC's JONATHAN KARL: http://abcn.ws/1g5sj51

REPUBLICANS TO OBAMA ON UKRAINE: 'WE TOLD YOU SO'. As the crisis in Ukraine continues to unfold rapidly, Republicans aren't waiting for the dust to settle before declaring that they saw it coming, ABC's ABBY PHILLIP notes. Predictions from the likes of President Obama's 2008 presidential opponents Sen. John McCain, R-Ariz., and Sarah Palin, and Obama's 2012 Republican presidential challenger Mitt Romney are making 2014 seem like a hangover of presidential election's past. Remember that hot mic moment in the heat of the 2012 elections when President Obama was caught promising Vladimir Putin more "flexibility" after he was re-elected? Well McCain does. "By the way, a couple of my favorites: 'Tell Vladimir that I'll be more flexible when I'm re-elected.' Tell Vladimir I'll be more flexible when I'm re-elected?" said McCain at the American Israel Public Affairs Committee conference in Washington yesterday, his voice dripping with sarcasm. "This is the ultimate result of a feckless foreign policy where nobody believes in America's strength anymore," he added. Indeed, it seems that those who have been beating the drum about Putin's cold war aspirations are feeling somewhat vindicated. http://abcn.ws/No9YJz

ANTI-INCUMBENCY HITS A 25-YEAR HIGH. Anti-incumbent sentiment has reached a 25-year high in the latest ABC News/Washington Post poll, with economic frustration damaging Barack Obama's Democrats while the Republican Party labors under a broad view that it's out of touch with the concerns of most Americans, ABC's GARY LANGER notes. The Republicans run evenly with the Democrats in congressional vote preference among registered voters, historically a strong position for the GOP given its advantage in midterm turnout. Perhaps more important, with control of the U.S. Senate at stake, the Republicans have a 50-42 percent advantage for Senate seats in the 34 states holding those contests. That said, the Tea Party is a substantial risk factor for the Republicans, the Democrats have gained back some ground since January on key issues - and the public's double-barreled discontent poses deep uncertainty for both political parties at this stage of the midterm contest. http://abcn.ws/1kTzm5a

-JUST 22 PERCENT OF AMERICANS ARE INCLINED TO RE-ELECT THEIR REPRESENTATIVE in Congress, the fewest since ABC/Post polls first asked the question in 1989. Instead this poll, LANGER notes, finds that 68 percent say they're ready to look around for someone new. That's 14 percentage points more than average, and while anti-incumbency has been close before - 66 percent last October - it's never been quite this high. Anti-incumbent sentiment is largely economic in nature; as such, while there's dissatisfaction with both parties, it's pointed more at the Democrats, given their control of the big chair at 1600 Pennsylvania Ave. Pro-incumbents favor the Democrat in their congressional district by a 14-point margin. Anti-incumbents favor the Republicans, by 8. Most damaging to the Democrats is that 72 percent of Americans still rate the economy negatively, more than five years into Obama's stewardship. While that's sharply down from its peak, 94 percent, as he took office, it's still a broad majority. Moreover, while 56 percent say the economy has begun to improve, that view has lost steam - and among those who do see a recovery, two-thirds say it's a weak one. http://abcn.ws/1kTzm5a

WHO'S TWEETING?

@WorldNews: For the latest updates on Crimea and Ukraine, follow @ABC's team on the ground in #Crimea: @TerryMoran and @MarquardtA

@GeraldFSeib: Late last year, Biden tried in series of calls to convince Ukraine's Yanukovych Russia was offering a bad deal: http://on.wsj.com/1cprXLn

@moody: When Sam Brownback discusses his ideal presidential nominee, he pretty much describes Sam Brownback. http://yhoo.it/1hIV6ji #2016

?@HotlineJosh: How toxic is Washington these days? Meet three members of Congress trading down for lower offices, via @HotlineScott http://www.nationaljournal.com/politics/trading-down-some-lawmakers-leaving-congress-for-lower-profile-jobs-20140303 …

@EvanMcSan: . @VP campaigning for @MichelleNunnGA in ATL today http://www.mcclatchydc.com/2014/03/04/220045/biden-hits-the-campaign-trail.html …