WASHINGTON — Two months before next week’s midterm elections, the Obama administration awarded the biggest share of almost $600 million in economic stimulus-based transportation grants to projects in districts with a Democratic congressman even though Republicans represent 34 more House districts across the country, an Associated Press analysis has found.

Applicants from Democratic-held districts won 48 percent of the so-called TIGER grants for road, bridge and rapid transit projects, rail line repairs and port upgrades. Just 33 percent of the Transportation Investment Generating Economic Recovery grants were awarded to GOP-held districts. The rest went to projects that cross district lines.

Republicans claim GOP-represented areas have been shortchanged every year since the TIGER grants were established in 2009 as a small part of President Barack Obama’s $840 billion stimulus package to help bring the U.S. economy out of a recession.

Democrats argue that more grants naturally go toward the pressing infrastructure needs of urban areas, where they continue to outnumber Republicans. But the pattern is nonetheless irksome for Republicans, who represent 54 percent of House districts nationwide.

“Just by the numbers one has to say that it looks like politics is involved because Democratic districts fare far better, significantly better than Republican districts,” said Sen. David Vitter, R-La.

Transportation Department spokesman Brian Farber insisted politics doesn’t play a role.

“TIGER is a merit-based, competitive program, and DOT funds the best projects that are submitted, no matter where they are located,” he said. “In fact, a number of Republicans championed projects in cities that are represented by Democrats and vice versa.