WASHINGTON — A day after it was unveiled, President Obama’s gun-control plan yesterday ran smack into the cold reality that it’s a hard sell even for some Senate Democrats.

“While I appreciate the president’s efforts to keep Americans safe, I believe the place to start is to enforce the laws on the books,” said Sen. Mark Pryor (D-Ark.), echoing other Democrats from rural, gun-loving states.

Obama’s proposals face stiff opposition in the Republican-run House. None is expected to gain traction without a push from the Democratic-led Senate.

Sen. Jon Tester (D-Mont.) backed Obama’s call for more background checks but raised doubts over the effectiveness of an assault-weapons ban.

“I will look closely at all proposals on the table, but we must use common sense and respect our Constitution,” he said.