Conventional wisdom in political circles is that President Bush has lost the support of the “Republican base” because of his handling of several key issues, especially immigration and government spending. Many political pundits are calling on him to court the base or risk losing control of Congress.

Evidence that Bush is actually in trouble with his base runs the gamut: More rational analyses point to polls that show Bush’s approval has fallen disproportionately lately among self-described Republicans, while other critics assert that Bush and his advisers are simply out of touch with real Republicans. One respected pundit, Peggy Noonan, recently advanced the curious conclusion that Bush simply doesn’t like the base.

I won’t deny the polling evidence, yet my own reading of the numbers is not as pessimistic as that of many GOP insiders. And I have a wholly different perspective on what Bush should do to improve the party’s electoral outlook. While some Republicans are recommending that the president do everything possible to woo the so-called base, I think that strategy would result in more lost seats than a strategy focused on building a winning coalition of Republicans and ticket-splitters.

After John Kerry lost the 2004 presidential election to Bush, many Democrats excoriated Kerry for his failure to excite his base. Kerry was Bush lite, they mocked, and that supposedly explained his fate. Kerry’s Democratic critics seemed to be saying that if he had just campaigned on a platform of sharply higher taxes, increased entitlements and pacifism, Bush would have fallen like a house of cards. Of course, when we Republicans hear talk like that we’re inclined to behave like an unruly crowd in the streets below someone on a top-floor window ledge threatening suicide. We’re yelling, “Jump!”

Yet for some reason the crowd that laughs at liberals’ pleas to “let Democrats be Democrats” doesn’t seem to recognize that the same strategy on our side of the aisle is equally inane. It was just a decade ago that the mob was calling on another needy Republican, Bob Dole, to do something that would ignite and motivate support from the base.

Dole and his running mate, Jack Kemp, rolled out a massive tax-cut plan. It was the centerpiece of the Dole-Kemp campaign. And the base just didn’t rally to the cause.

I recall doing some post-election analysis in suburban Detroit counties. It was clear that even young conservative families, many that would have richly benefited from the child tax credit that Dole proposed, were uninspired. They didn’t even bother to go to the polls.

My belief is that Dole’s plan marginalized him in the minds of many voters. Critics in the mainstream press characterized it as irresponsible and likely to increase the deficit.

Others suggested Dole’s desperate ploy to mollify his base was evidence his candidacy had no chance. How serious can you be about a candidate’s prospects when his own partisans have to be given a rebate to vote for him? It made Dole look like a sure loser to a most Americans, but particularly to ticket splitters.

Do the math. Though numbers vary across the country, the typical scenario is that about 35 to 40 percent of likely voters are Republicans. Democrats control a comparable percentage of the electorate. So 20 to 30 percent of voters are independent ticket splitters. If Bush builds everything around “the base,” Republicans won’t muster a minimum winning coalition of 50 percent plus 1.

Republicans must appeal to a sizable percentage of independents. That’s just as important as appealing to the base if the party wants to maintain control of Congress in November.

Hill is director of Hill Research Consultants, a Texas-based firm that has polled for GOP candidates and causes since 1988.