If Congress' latest attempt to overhaul the nation's immigration laws fails, it might be hard to blame Democrats.
In 2007, the last time lawmakers took up immigration reform, 15 Senate Democrats joined together with a majority of Republicans to derail a major bill. But this year, Democrats in the Senate have shown few signs that they will splinter like that again.
On Monday, every Senate Democrat voted yes on a key test vote on the bill, including a handful from red states who helped sink the 2007 legislation. The vote, which limited debate on a border security amendment, passed 67-27.
That amendment was crafted by two Republicans and was meant to pacify skeptical GOP senators who were concerned that the bill didn't go far enough to secure the U.S.-Mexico border. But the measure quelled the fears of some Democrats, too, according to one of its authors.
"I'm not going to mention names, but there was no question some conservative Democrats had concerns about border security," Sen. Bob Corker (R-Tenn.) told reporters after the vote on Monday. "I do think this strengthened the bill in their eyes also."
A handful of Democrats thought of as holdouts on the bill voted to advance the amendment. That includes members who had blocked the 2007 bill, like Sen. Max Baucus (D-Mont.) and Mark Pryor (D-Ark.)
One of the reasons that some centrist Democrats voted against the 2007 bill was because they believed the border security provisions were lax. They pressed for stricter measures to be included in this bill, and their requests appear to have been met.
Some liberal Democrats also stood in the way of the 2007 bill over its guest-worker program, which they believed could undercut American workers. But the low-skilled worker program in the current bill was the result of a compromise between major business and labor groups, and liberal resistance to the overall bill is very limited.
Independent Sen. Bernie Sanders (Vt.), who caucuses with the Democrats, voted against the legislation six years ago over the guest-worker proposal. He's expressed concern that the current bill could have a negative effect on U.S. workers. But on Monday he voted yes to advance the border amendment after he won the inclusion of a $1.5 billion youth jobs program.
That's not to assume that Senate Democrats will vote unanimously to pass the immigration bill. A yes vote on Monday's procedural motion does not mean that all the concerns of undecided Democrats have been answered.
But there is no question Democrats are more united on immigration this time around than six years ago. Liberals say that the bill's provisions on a pathway to citizenship and low-skilled workers are more friendly now than they were in 2007, when George W. Bush was president.
The political climate around immigration is also different this time around, with both left- and right-leaning groups selling the bill to voters.
"I think that the labor movement deserves some credit for making it clear to working-class people of all races that immigration and a path to citizenship will help all working people," said Jeff Hauser, a spokesman for the AFL-CIO, which opposed the 2007 bill but supports this year's proposal. "It's a lot easier to assemble Democrats from places like West Virginia and Montana for this bill."
Minimal Democratic resistance removes a key roadblock that helped tank immigration reform the last time around in the Senate. That, however, does not mean that passage of immigration reform is a sure thing.
The Senate appears likely to approve the bill this week. But the House of Representatives, which is controlled by Republicans, has shown little appetite for passing a comprehensive bill like the one in the Senate. The biggest stumbling block is that the legislation includes a path to citizenship for undocumented immigrants, a must for Democrats and immigrant-rights groups.
The Senate bill's backers are hoping to pass it with as many as 70 yes votes, a total they believe can spur House GOP leaders to change their tune. But in the event immigration does fail in the House, left-leaning groups are preparing to lay blame at the feet of Republicans alone if Democrats remain united.
"House Republicans are much closer to their moment of truth," Frank Sharry, executive director of the pro-immigration reform group America's Voice, said in a statement on Monday. "They either find a way to pass reform or find themselves blamed for blocking it."