As Sen. John Kerry learned in last year's presidential race, it's not always easy defending a congressional voting record.

The Massachusetts Democrat got tagged with being a "flip-flopper" for seemingly conflicting votes on a range of issues, most notably the Iraq war. Now it's Maine's two Republican senators who are feeling similar heat, having to defend votes in favor of the budget outline for the next fiscal year.

The budget, which won approval in the Senate 52-47, contained cuts to programs that made both Sens. Olympia Snowe and Susan Collins uneasy. The most contentious of these are planned reductions for Medicaid health insurance for the poor. The budget also advances the agenda of those who would like to open Alaska's Arctic National Wildlife Refuge to oil drilling, something Snowe and Collins oppose.

Those are just the highlights, really, of a budget that has plenty to dislike, not the least of which is the fact that, despite some painful cuts in Medicaid and other programs, the budget makes little significant progress on reducing the size of the federal deficit.

What the budget did have, however, were some provisions that will help Bath Iron Works as it competes for contracts to build the Navy's next generation of destroyers. The budget alters the funding mechanism for the ships to allow more to be ordered up front. It also expresses congressional disapproval of the idea of having a single shipyard build the destroyers. There are currently two slated to do so.

So, despite much that the senators disliked about the budget, they gave it their approval. Its passage is significant in the Senate, because it means that future spending bills will only require a simple majority rather than the 60 votes it normally takes to end discussion on a bill.

The vote is a good illustration of the tough choices a lawmaker sometimes has to make. Issues are rarely considered in isolation. Instead they're packaged together in a deliberate attempt to attract votes from a majority.

In voting for this budget (Maine's two House members, Democrats Tom Allen and Michael Michaud, voted against it), Snowe and Collins put the health of Bath Iron Works ahead of other issues.

That may give political opponents ammunition, but it's also defensible. Over time, it's up to the voters to decide if such decisions were the right ones.