HARRISBURG — Sen. Bob Casey reported about $4.4 million in his campaign account to begin 2012 as he gears up his re-election campaign against a crowded field of potential Republican challengers, including one who had slightly more money to spend.

Casey, a Democrat, raised almost $1.1 million in the last three months of 2011. Tuesday was the deadline for candidates to file a campaign finance report with the Federal Election Commission. The report figures were current as of Dec. 31.

Tom Smith, who has already invested $5 million of his own money into his campaign, had slightly more to spend, with almost $4.5 million. Smith is among at least four candidates who are seeking the Republican nomination to challenge Casey in the fall. The primary election is April 24.

The endorsed Republican Party candidate, Steve Welch, has said he had $1 million on hand after loaning his campaign the same amount, while former state Rep. Sam Rohrer had about $69,000.

Meanwhile, U.S. Rep. Jason Altmire padded his funding edge over fellow Democratic U.S. Rep. Mark Critz in a heated southwestern Pennsylvania primary. The two Democrats are running against each other under a newly drawn map created by Republicans that effectively combines Critz’s and Altmire’s current districts.

Altmire reported about $852,000 on hand, compared with Critz’s $465,500, as of Dec. 31. A spokesman for Critz said the congressman has since raised more than $200,000 in cash and commitments.