Four Democratic senators facing tough reelection fights voted in favor of the immigration reform measure on Thursday afternoon, opening themselves up to likely attacks from conservatives heading into 2014 and beyond.

ADVERTISEMENT
Sen. Mark PryorMark PryorMedicaid rollback looms for GOP senators in 2020 Cotton pitches anti-Democrat message to SC delegation Ex-Sen. Kay Hagan joins lobby firm MORE (D-Ark.), a top GOP target in 2014, voted to advance the bill along with vulnerable Sens. Mark BegichMark Peter BegichPerez creates advisory team for DNC transition The future of the Arctic 2016’s battle for the Senate: A shifting map MORE (D-Alaska), Kay HaganKay HaganLinking repatriation to job creation Former Sen. Kay Hagan in ICU after being rushed to hospital GOP senator floats retiring over gridlock MORE (D-N.C.) and Mary LandrieuMary LandrieuYou want to recall John McCain? Good luck, it will be impossible CNN producer on new O'Keefe video: Voters are 'stupid,' Trump is 'crazy' CNN's Van Jones: O'Keefe Russia 'nothingburger' video 'a hoax' MORE (D-La.)  

Sen. Al FrankenAlan (Al) Stuart FrankenThe Hill's 12:30 Report The Hill's 12:30 Report John Oliver rips AT&T-Time Warner merger MORE (D-Minn.), who is also up for reelection but considered less vulnerable, also voted for the bill. No Democrats voted against the legislation. 

A handful of Republicans in blue and swing states — some of who could see primary challenges — voted for passage.

Sen. Lindsey GrahamLindsey Olin GrahamDurbin: I had 'nothing to do' with Curbelo snub Republicans jockey for position on immigration Overnight Health Care: House passes 20-week abortion ban | GOP gives ground over ObamaCare fix | Price exit sets off speculation over replacement MORE (S.C.), up for reelection in 2014, voted for the bill. 

He has long faced criticism from conservatives for his record, though no primary challenger has yet emerged, and he's long been an outspoken supporter of reform. 

Sens. Kelly AyotteKelly Ann AyotteDems plan to make gun control an issue in Nevada Stale, misguided, divisive: minimum wage can't win elections Trump voter fraud commission sets first meeting outside DC MORE (N.H.), Marco RubioMarco Antonio RubioOvernight Defense: Tillerson, Trump deny report of rift | Tillerson says he never considered resigning | Trump expresses 'total confidence' in secretary | Rubio asks Army to kick out West Point grad Rubio asks Army to kick out West Point grad with pro-communist posts GOP establishment doubts Bannon’s primary powers MORE (Fla.) aren't up for reelection until 2016, but their support for the reform measure is already causing consternation among conservatives.

Most notably, Tea Party leader Sarah Palin suggested the two should face primary challenges. 

And Rubio, who is seen as a probable 2016 contender, has seen his poll numbers drop in the past month, as debate over the bill intensified. 

Critics say his role in crafting and selling the measure to the public could hurt him with Republican primary voters and jeopardize his presidential aspirations.

Also up for reelection in 2016 is Sen. Mark KirkMark KirkGiffords, Scalise highlight party differences on guns Stale, misguided, divisive: minimum wage can't win elections Immigration critics find their champion in Trump MORE (R-Ill.), whose vote for the bill could help him appeal to centrist voters in his blue state. 

Sen. Dean HellerDean Arthur HellerNevada senators urge airlines to enact new policies after Las Vegas shooting Dems plan to make gun control an issue in Nevada GOP establishment doubts Bannon’s primary powers MORE (R-Nev.), up in 2018 in a swing state, will also need to appeal to that voting bloc.

GOP debate over the bill has highlighted a split within the party on reform. Conservatives generally oppose what they say is a temporary stop-gap measure that does little to solve the problem and offers inadequate border security provisions. 

The no-votes from National Republican Senatorial Committee Chairman Jerry MoranGerald (Jerry) MoranTIMELINE: The GOP's failed effort to repeal ObamaCare The Hill's Whip List: Republicans try again on ObamaCare repeal IT modernization measure included in Senate-approved defense policy bill MORE (Kans.) and his NRSC deputies, Sens. Rob PortmanRobert (Rob) Jones PortmanOvernight Cybersecurity: Equifax security employee left after breach | Lawmakers float bill to reform warrantless surveillance | Intel leaders keeping collusion probe open Reddit hires first lobbyists Senate panel approves bill compelling researchers to ‘hack’ DHS MORE (Ohio) and Ted CruzRafael (Ted) Edward CruzWhatever you think the Alabama special election means, you’re probably wrong This week: Congress gets ball rolling on tax reform Week ahead: Senators work toward deal to fix ObamaCare markets MORE (Texas), underscore what a politically perilous issue immigration may be for some Republicans going forward.

In the House, a large contingent of far-right members have pledged to oppose the Senate measure.