A fear of voting has gripped Democratic leaders in the Senate, slowing the chamber's modest productivity this election season to a near halt.

With control of the Senate at risk in November, leaders are going to remarkable lengths to protect endangered Democrats from casting tough votes and to deny Republicans legislative victories in the midst of the campaign. The phobia means even bipartisan legislation to boost energy efficiency, manufacturing, sportsmen's rights and more could be scuttled.

The Senate's masters of process are finding a variety of ways to shut down debate.

Senate Majority Leader Harry Reid, D-Nev., now is requiring an elusive 60-vote supermajority to deal with amendments to spending bills, instead of the usual simple majority, a step that makes it much more difficult to put politically sensitive matters into contention. This was a flip from his approach to Obama administration nominees, when he decided most could be moved ahead with a straight majority instead of the 60 votes needed before.

Reid's principal aim in setting the supermajority rule for spending amendments was to deny archrival Sen. Mitch McConnell a win on protecting his home state coal industry from new regulations limiting carbon emissions from existing power plants. McConnell, the Senate Republican leader, faces a tough re-election in Kentucky.

This hunkering down by Democrats is at odds with the once-vibrant tradition of advancing the 12 annual agency budget bills through open debate. In the Appropriations Committee, long accustomed to a freewheeling process, chairwoman Barbara Mikulski, D-Md., has held up action on three spending bills, apparently to head off politically difficult votes on changes to the divisive health care law as well as potential losses to Republicans on amendments such as McConnell's on the coal industry.

"I just don't think they want their members to have to take any hard votes between now and November," said Sen. Mike Johanns, R-Neb. And there's "just no question that they're worried we're going to win some votes so they just shut us down."

Vote-a-phobia worsens in election years, especially when the majority party is in jeopardy. Republicans need to gain six seats to win control and Democrats must defend 21 seats to the Republicans' 15.

So Sen. Tom Harkin, D-Iowa, probably shouldn't have been surprised when his cherished bill to fund the Labor, Education and Health and Human Services departments got yanked from the Appropriations Committee's agenda this month. Word quickly spread that committee Democrats in Republican-leaning states feared a flurry of votes related to "Obamacare."

"It's not as if they haven't voted on them before," Harkin griped. "My way of thinking is, 'Hell, you've already voted on it. Your record's there.'" Harkin blamed Senate Democratic leaders.

Two other appropriations bills have run aground after preliminary votes. The normally non-controversial energy and water bill was pulled from the committee agenda after it became known that McConnell would have an amendment to defend his state's coal mining industry. McConnell is making that defense a centerpiece of his re-election campaign and his amendment appeared on track to prevail with the help of pro-energy Democrats on the committee.

Again, after consulting with Reid, Mikulski struck the bill from the agenda.

McConnell pressed the matter the next day, this time aiming to amend a spending bill paying for five Cabinet departments. Democrats again headed him off.

Democrats privately acknowledge that they're protecting vulnerable senators and don't want McConnell to win on the carbon emissions issue. They also see hypocrisy in McConnell's insistence on a simple majority vote for his top — and controversial — priority while he wants Democrats to produce 60 votes to advance almost everything else.

Another measure, financing the Treasury Department and Internal Revenue Service, failed to get a committee vote last week after speeding through a subcommittee hearing. Mikulski blamed problems with timing. But it was known that Republicans had amendments on hot-button issues coming.

Fear of voting is hardly new. In the last two years of the Clinton administration, Majority Leader Trent Lott, R-Miss., blocked Democrats from offering a popular Patients' Bill of Rights, and more. At the time, Charles Schumer of New York and Dick Durbin of Illinois were among the Democrats who cried foul.

These days, Durbin and Schumer hold the No. 2 and No. 3 Democratic Senate leadership posts and now that their party is running the place, they're backing Reid's moves to clamp down on GOP amendments.

"You've always got senators on both sides of the aisle of all political persuasions and all regions whining and complaining how they don't want to vote on this amendment or that amendment," Lott says now. "It always frankly agitated me because I felt like these are big boys and girls." He said "it has gotten worse and worse and worse."

Republicans say Democratic leaders are trying especially to protect Mark Begich of Alaska, Mark Pryor of Arkansas and Mary Landrieu of Louisiana. Landrieu says she hasn't asked for such help.

"I've taken so many hard votes up here," Landrieu said. "I could take more."