Washington ? Cast this debate as big banks versus big government.

Despite lingering public anger at Wall Street, most congressional Republicans oppose the tougher financial regulations that Congress is expected to send to President Barack Obama this week.

The GOP is betting that the bill’s ambitious goals will be lost on voters and instead feed an election-year narrative that Democrats stand for bigger, more intrusive government.

Republicans are throwing up a final procedural roadblock to the bill today. The sweeping regulatory overhaul is expected to make it through the Senate with the minimum of 60 votes. Only three Republicans have voiced their support.

Not too long ago, senators from both parties imagined a bill with broad bipartisan support that reflected a consensus that the financial sector needed a new set of rules. These days, though, Republicans liken the legislation to Obama’s health care legislation and the $862 billion economic stimulus package — two initiatives that have not rallied public support.