Judging from his record, Tim Scott will be a principled conservative in the U.S. Senate. And his political — and personal — history also indicates that he also will be a resolute optimist. Good for him.

Rep. Scott, who has earned high marks from colleagues on both sides of the U.S. House aisle, can make a positive impact in the U.S. Senate, too.

Though Republicans are often scorned as prophets of gloom (especially after losing back-to-back presidential elections), Mr. Scott consistently accentuates the positive.

Such was the encouraging case again Monday at the Statehouse. Gov. Nikki Haley had just revealed her decision to, in effect, promote Mr. Scott from 1st District congressman to U.S. senator as the replacement for Jim DeMint.

Mr. Scott proclaimed, in his upbeat response: “The future is incredibly bright for America. We have our challenges, we have our things that we have to overcome. But, boy, does the future look great in South Carolina.”

OK, so Mr. Scott was also painfully blunt in warning that the U.S. economy is still “definitely and definitively on the wrong track.” He even reiterated the familiar alarm about the unsustainable growth of the federal government:

“We have a spending problem, ladies and gentlemen, and not a revenue problem. It is very difficult for us to fix the problem in a nation with $16 trillion in debt and an annual deficit of more than $1 trillion talking about raising revenue from the top 2 percent. We could take all the revenue on top 2 percent and could not close the annual deficit.”

And we could take all the other possible replacements for Sen. DeMint and not find anyone as qualified as Mr. Scott for this high-stakes task.

During 13 years on County Council, two in the S.C. House and the last two in the U.S. House, Mr. Scott has blended solid conservative ideals with practical realities. As County Council chairman, he was particularly adept at forging compromises across party lines.

He is also a trailblazer. By winning the 1st District House seat in 2010, he became South Carolina’s first black Republican congressman since the 19th century.

Now, by virtue of Gov. Haley’s appointment, he will become South Carolina’s first black senator — and the first black senator from the South since Blanche Bruce of Mississippi in 1881.

On Thursday in Columbia, Rep. Scott paid touching tribute to his mother Frances, who raised him in modest circumstances after his father left. That proud North Charleston mom, despite working long days (and nights), gave our future senator an abundance of parental caring — and firm guidance. As Mr. Scott put it, she “believed that sometimes love has to come at the end of a switch.”

Gov. Haley deserves credit not just for picking him but for resisting the temptation to appoint a mere “placeholder” to serve until the 2014 election that will decide who finishes Sen. DeMint’s second term.

Indeed, Rep. Scott, who moves up on Jan. 3, said Thursday that he intends to run in that election.

First, though, there must be a special House election to determine Rep. Scott’s successor.

Despite our enthusiasm for his move to the Senate, we recognize the disappointment felt by some voters who gave Rep. Scott a second House term by a large margin last month. At least he will still be serving in elective office.

In contrast, Mr. DeMint, after winning a second Senate term by a large margin in 2010, has violated an inherent pledge by walking out on that job — with four years left — to become president of the Heritage Foundation.

As for Mr. Scott’s new title, it might take some folks a while to get used to it.

But we suspect he will adjust to being called “Sen. Scott” rather easily.

That’s because 16 years ago, he aspired to that title — on the state level. While still a rookie on Charleston County Council, Mr. Scott challenged Democratic state Sen. Robert Ford in a heavily Democratic district — and suffered a 65-35 percent thumping from the incumbent.

Yet Mr. Scott typically found a silver lining around the dark cloud of that landslide loss. As he explained on that 1996 Election Night: “Effort is never wasted. This was just a delay, not a defeat.”

Now he’s going to be a senator after all — only in Washington, not Columbia.

So congratulations to Mr. Scott — and to Mrs. Haley.

The governor had an obligation to pick the best replacement available.

And that she did.