It’s been more than four years since former Rep. Joe Sestak narrowly lost his bid for Senate — and the Pennsylvania Democrat hasn’t stopped running since. After his 2010 loss to Republican Patrick J. Toomey, Sestak continued to traverse the state to raise cash before officially filing for a rematch against the senator in September.  

“We’ve done 400 events in two years for other candidates,” Sestak said in a Wednesday phone interview with CQ Roll Call. “I’ve put a quarter-million miles on my car.”  

Keystone State Democrats laud Sestak for coming within 2 points of defeating Toomey in an otherwise miserable year for the party. But some privately question whether he’s the party’s best bet for a high-stakes Senate race. So far, top state Democrats are mum on whether they would support Sestak in a competitive primary.  

“Oh it’s way too early to talk about support,” Sen. Bob Casey, D-Pa., said when asked about Sestak’s bid. “It’s real early. But all I can predict is ’16’s going to be better than ’14.”  

“He got close last time,” said outgoing Rep. Allyson Y. Schwartz, D-Pa. “But I think people are also open to other names, so there could well be a primary.”  

Toomey sits near the top of Democrats’ target list in 2016. President Barack Obama carried Pennsylvania by a 5-point margin in his last campaign. Former Secretary of State Hillary Rodham Clinton remains popular there, and she would top the ticket if she runs for president. Either way, Toomey will need to attract a swath of split-ticket voters to win re-election.  

In 2010, Sestak defeated Sen. Arlen Specter in a pricey primary fight. Pennsylvania Democrats were fully behind Specter, formerly a moderate Republican who switched parties to avoid a primary with Toomey. This situation — and Sestak’s pugnacious personal style — have created an awkward relationship with some top Pennsylvania Democrats.  

If Toomey looks vulnerable, it’s easy to see other Democrats piling into a primary.

Sestak said he’d welcome primary opposition. “I think anybody who wants to get in should get in,” he said.  

But here’s the big question for Pennsylvania Democrats: Who else could run?  

A number of Democrats on the Keystone State bench took themselves out of consideration days after the 2014 elections. That includes Democrats in the delegation, which has waned in recent cycles.  

“We could have a meeting in a phone booth,” Rep. Matt Cartwright, D-Pa., joked before the Thanksgiving recess.  

Cartwright was an emphatic “no” on a Senate bid.  

“Admiral Sestak and I are close friends,” Cartwright said. “I would regard it as a supreme betrayal on my part to run against him, since he’s already announced for the position.”

State Treasurer Rob McCord, who also ran unsuccessfully in the gubernatorial primary, took himself out of the mix . Katie McGinty, another failed gubernatorial candidate, recently took a job as Gov.-elect Tom Wolf’s chief of staff  — a strong indication she has no plans to run for Senate in 2016.  

Democrats say two potential candidates remain on the bench: Attorney General Kathleen Kane and Montgomery County Commissioner Josh Shapiro.  

But Kane’s stock has slumped . Democrats have criticized her job performance as the state’s top prosecutor, and she is currently under investigation for breaking grand jury secrecy rules by allegedly giving information to a newspaper.  

Shapiro remains a strong contender, but Democrats wonder whether he is eyeing other statewide office. An interview request left for Shapiro at his office was not returned.  

The Democratic Senatorial Campaign Committee — tasked with helping Democrats take back the majority they lost in 2014 — declined to discuss recruitment in Pennsylvania.  

“Pat Toomey’s rabidly partisan and irresponsible record as a senator is wildly out of step with Pennsylvania and any number of Democratic candidates can beat him,” DSCC spokesman Justin Barasky said. “But it’s so early in the cycle that we aren’t even in 2015 yet let alone 2016.”  

Rep. Mike Doyle, D-Pa., similarly declined to talk about the contest.  

“I don’t celebrate Christmas before Thanksgiving,” the Pittsburgh-based Democrat said. “I don’t discuss Senate races that are two years away.”  

Toomey declined to say which Democrat he’d rather face in his quest for re-election. Instead, he told CQ Roll Call he’s keeping his eye on starting the 114th Congress with a newly minted GOP Senate majority.  

“I don’t know who my opponent is going to be, and I am not focused on that. That is two years away,” Toomey said Tuesday after the weekly GOP conference lunch. “We’re about to have an extraordinary opportunity to actually reopen the Senate and to actually govern. I am looking forward to that, I think it’s going to be a very active time, I hope a very productive time, and that’s what I’m focused on.”  

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