3 Congressional Races That Still Don't Have a Winner

— -- With House freshmen reporting to Washington this week for orientation, three Congressional races from last week still remain too close to call.

In Arizona, Gabby Giffords’ former seat is still up for grabs, with the re-match between endangered Democrat Rep. Ron Barber and Republican former Air Force Col. Martha McSally now moving to a recount.

Two California districts that have dealt with severe droughts are still waiting for races to be called, both including fierce challenges from Republicans against incumbents.

It all means the Republican wave this election may still be able to nab three more seats before the end of this week.

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Here’s a look at where the races stand:

Arizona’s 2nd Congressional District: Ron Barber vs. Martha McSally

All the votes have been counted in Arizona's 2nd Congressional District, but the battle is still on between Democratic Rep. Ron Barber and Republican challenger Martha McSally. It's been one of the most closely watched House races this midterm election, in no small part because of the razor-thin margin the congressman won by in his 2012 matchup with McSally. But the less-than-2,500 vote edge he had in that victory seemed stout compared to the final vote count in the rematch this year. The election results placed McSally ahead by just 161 votes. According to Arizona law, a candidate must win by a margin of .10 percent. McSally held a .08 percent edge over her opponent, setting the stage for the state's first automatic recount in a congressional election and its closest race in history. According to the Arizona secretary of state's office, the recount will not begin until at least Dec. 1.

California’s 7th Congressional District: Ami Bera vs. Doug Ose

California’s 7th Congressional District isn’t new to nail-biters: Rep. Ami Bera, a Democrat, won a tight race against Republican incumbent Dan Lungren just two years ago. Before the 2012 election, the 7th District was rearranged to fit the Sacramento suburbs more neatly into its territory, meaning Bera could take advantage of a more liberal populace. But this year, Republican challenger and former Rep. Doug Ose fought tooth and nail to retake the seat for the GOP. What could explain the dead heat? Ose’s former district now makes up 70 percent of the 7th District, meaning the gerrymandering that once helped Bera is now benefitting Ose. As of Wednesday, Bera held a 711-vote lead over Ose, leaving the race too close to call as provisional ballots are still being counted.

California's 16th Congressional District: Jim Costa vs. Johnny Tacherra

In California’s heavily Hispanic and agriculture-driven 16th Congressional District, Democratic incumbent Jim Costa holds onto just a 75-vote lead over Republican challenger Johnny Tacherra. The Fresno Bee reported that another updated vote count was expected today. Tacherra’s competitiveness in the race gave him enough confidence to fly to Washington this week to attend congressional orientation for new members despite knowing he could actually lose his race. According to the National Review, Tacherra decided to run against Costa after a tense meeting with him in his Capitol Hill office regarding droughts in their district, a contentious issue in a growing number of California elections. A third-generation dairy farmer, Tacherra ran the close campaign with just a single staffer whom he paid $500 a month.