Sen. Bob Dole, the new Senate majority leader, is an object lesson in the importance of tenacity as a human and political trait. When he was shot up by the Germans in World War II, his wounds were so severe that anyone without his fierce determination to live would probably have succumbed.

Instead, he fought his way back through repeated operations and 39 months of hospitalization, finished school, and with his new law degree went into politics in Kansas. In the world of electioneering, where the firm right-hand handshake is the basic tool of the trade, Dole -- with his withered, shrapnel-riddled right arm -- endured the hundred-times-a-day awkwardness of having to reach across with his left hand to take the voter's profferred hand -- and laughed away the embarrassment.

When he was the vice presidential candidate on the losing Republican ticket in 1976, the designated hatchet man for nice-guy Jerry Ford, it seemed likely to be his final fling in national politics. But Dole was adamantly unwilling to accept as his political epitaph the judgment of the political world that he had fouled out of the vice presidential debate with Walter Mondale. Instead, he bounced back with a superb, self-mockingly humorous speech at the Gridiron Club dinner, and became more of a power in the Senate than ever before.

He tried for the Republican presidential nomination in 1980, with little staff and less money, and was humiliated. But as chairman of the Senate Finance Committee for the past four years -- and a key player on the Judiciary Committee as well -- he has been as effective a legislator as the Senate can boast.

In selecting Dole from the field of five contenders for the majority leadership, the Republican senators went to their strength. They picked someone who will strengthen their party in Washington and the nation in the months and years ahead.

Along with Sen. Alan Simpson of Wyoming, the newly elected whip, the Republicans now have a leadership team as wise and witty, as humane and as humorous, as the Senate has ever seen. It is a team that will be at least a match for the Democratic duo of Minority Leader Robert C. Byrd of West Virginia and Minority Whip Alan Cranston of California on legislative tactics and vastly superior as television spokesmen for their party.

Although both Dole and Simpson are partisans to the core, both are men who have demonstrated repeatedly their willingness to reach across the aisle to work with Democrats on matters of large national importance. Dole joined with liberals such as George McGovern to back overseas and domestic food relief programs and Ted Kennedy to aid civil rights. Simpson is best known to the country as the Republican cosponsor of the bipartisan immigration reform bill that came close to passage in the last Congress.

Their large-mindedness can be a considerable asset to President Reagan, if he chooses to seek a bipartisan approach to such issues as the budget deficit. Their election is evidence of the dominance in the incoming Senate of what might be called "the responsible center" of the political spectrum and the subordination -- for now, at least -- of both right-wing and left-wing ideologues.

But thus far, Reagan has given no evidence of adopting the "grand coalition" approach to budgetary and other issues that David Stockman, almost alone among his senior aides, has been urging. On the contrary, he seems to be headed down a path that will lead to confrontation with Congress. And there is a distinct possibility that his first confrontation will be with Dole.

The senator from Kansas, who yearns to be Reagan's successor, has never hesitated to express his disagreement with some of Reagan's fiscal policies -- especially the president's belief in the magic elixir of ever-lower tax rates. Dole does not disguise the fact that he thinks big budget deficits are a real and present economic danger.

Nor is Dole alone in the intellectual independence he has displayed. As a result of the re- shuffling of committee chairmanships following Dole's elevation, the major economic policy centers of the Senate now will be held by politicians who are anything but rubber stamps for the president.

Bob Packwood of Oregon, one of the most outspoken critics of Reagan's social and domestic policy views, succeeds Dole as chairman of the tax-writing Finance Committee. The other major money committee, Appropriations, is chaired by Packwood's Oregon colleague, Mark Hatfield, a skeptic on Reagan's defense buildup. Two other key economic panels, Budget and Commerce, are headed by two notably independent and moderate figures, respectively, Pete V. Domenici of New Mexico and John Danforth of Missouri.

Make no mistake. The president is not facing a hostile Republican leadership in the Senate. But neither is it a docile leadership. It is intellectually sharp, politically pragmatic, and ideologically middle ground. That is good news for the country. And it can be good news for Reagan, if he sees it as an opportunity and not a threat.