Republican Pat Toomey has opened a 10-point lead over Democrat Joe Sestak among likely voters in a critical US Senate race in Pennsylvania dominated by economic worries, according to a Reuters/Ipsos poll released on Tuesday.

Toomey, a conservative former congressman, leads Sestak, a former admiral elected to Congress in 2006, by 47% to 37% barely two months before the Nov. 2 election to replace Democrat Arlen Specter.

Toomey’s lead was smaller, 40% to 37%, among a larger pool of registered voters.

Sestak’s troubles in Pennsylvania are another warning sign for Democrats ahead of the congressional elections in which they face potentially big losses in the Senate and the possible loss of their majority in the House of Representatives.

Pennsylvania’s high-profile Senate race is one of more than a dozen contests that could determine whether Republicans gain the 10 Senate seats they need to regain control of the Senate and slam the brakes on President Barack Obama’s legislative agenda.

Voters in Pennsylvania, a crucial political battleground state won by Obama in 2008, said they were pessimistic about the state’s direction and unhappy with Democratic Governor Ed Rendell’s job performance.

A majority of voters, 55%, said the state was on the wrong track and only 37% believed it was headed in the right direction. Rendell’s job performance as governor won approval from only 43%, with 52% disapproving.

The struggling economy was the biggest problem on the mind of Pennsylvania voters by far, with 48% putting it at the top of the list over the budget deficit, which was second at 16%.

The little-known Sestak beat the veteran Specter in the Democratic primary in May for the right to take on Toomey, the former head of the conservative anti-tax group Club for Growth.

Obama had endorsed Specter but a majority of 59% of registered voters said Obama’s backing of Specter made no difference in their decision on how to vote.

In the governor’s race, Republican Tom Corbett led Democrat Dan Onorato among likely voters by a commanding 15 points, 49% to 34%.

The Ipsos poll of 600 registered voters, including 407 who said they were likely to vote, was taken Friday through Sunday.

Interviews were conducted in English and Spanish.

The full survey of registered voters had a margin of error of 4 percentage points. The smaller sample of likely voters had a margin of error of 4,9 percentage points.